U.S. Pat. No. 4,992,995 discloses a method for attenuating noise in seismic data. The method comprises obtaining a set of seismic data sorted into gathers of seismic signals, aligning selected coherent events, sorting the gathers in order to disorder the sequential order of the seismic signals in each gather, filtering the disordered gathers with a spatial filter, resorting the filtered signals in their original order, and combining the filtered signals with a respective gather of seismic singles to obtain a gather of seismic signals that is substantially free of unwanted coherent and random noise.
U.S. Pat. No. 5,237,538 also discloses a method of removing coherent noise from seismic traces.
U.S. Pat. No. 5,392,213 discloses a method for suppressing coherent noise from seismic or borehole data, which method comprises horizontally aligning the traces, comparing the amplitude, phase and/or shape of neighbouring traces, and subtracting traces from neighbouring traces only when the local correlation is high.